This invention relates to storage devices for use with data processing systems, and more particularly to a memory system providing content addressability of blocks of stored data.
Such memory systems have become increasingly important in modern data processing systems, particularly as an interface between main memory and bulk storage in the implementation of a virtual memory concept. Essentially, such a memory system provides blocks of data words which become accessible in response to an identifying tag presented to the memory system.
In the past, content addressable memory systems have generally been provided by means of mechanical access storage devices such as disk files used in conjunction with extensive software. The mechanical access devices themselves are disadvantageous because they involve moving parts, relatively large amounts of power, and relatively slow access times in comparison to the demands of modern data processing systems. Moreover, the software technique utilized involve extensive bookkeeping and problems of synchronization. They further result in undesirably slow associative search times and block transfer times.